Procedure and apparatus for metal drawing



Apn'il 28, 1953 1 w. E. KERR 4 PROCEDURE AND APPARATUS FOR METAL DRAWINGFiled June 27, 1945 7 Sheets-Sheet l Wallace Ker 1 ATTOPNE 7.

April 28, 1953 w. E. KERR 2,636,594

PROCEDURE AND APPARATUS FOR METAL DRAWING Filed June 27, 1945 7Sheets-Sheet 2 IN v /v TOE. A L Wa//ace E. Kerr: I'll/ /,l

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April 28, 1953 w. KERR PROCEDURE AND APPARATUS FOR METAL DRAWING FiledJune 27, 1945 7 Sheets-Sheet 5 r r 0 5 "6 U 6 Tr (N V g N e w m Wm I N aT I A 3 a 5 6 5 W 5 2 4 5 n Y n a! B d w k 4 4 9 6 3 4. 7 v 4.. n a 5 \79. 4 6 6 2h 5 0 6 mn I 5E: Ila:- ZE ll M. 5F 8 6 6 g m a F April 28,1953 w. 'E KERR 2,636,594

. PROCEDURE AND APPARATUS FOR METAL DRAWING Filed June 27, 1945 7Sheets-Sheet 4 [NVEN TOE.

Wallace 5. Keri: BY

AMWFM A T TOE'NE Y.

-W. E. KERR PROCEDURE AND APPARATUS FOR METAL DRAWING Filed June 2'7,1945 April as, 1 953 '7 Sheets-Sheet 5 FIE" INVENTOR. Wallace [5 Kerr BYj April 28, 1953 w. E. KERR 2,636,594

PROCEDURE AND APPARATUS FOR METAL DRAWING I Filed June 27, 1945 7Sheets-Sheet 6 I N V EN TOR. llr/lace 5 Kerr.

April 23, 1953 I w. E. KERR 2,636,594

PROCEDURE AND, APPARATUS FOR METAL DRAWING Filed June 27, 1945 7Sheets-Sheet 7 //L/ l7 W 7 M F: g 25 F: g 27 lmfw ATTO DNEK Ibpul:

Patented Apr. 28, 1953 UNITED STATES PATENT OFFICE PROCEDURE ANDAPPARATUS FOR METAL DRAWING Claims.

This invention relates primarily to procedure and apparatus to beemployed in metal drawing operations.

An object of this invention is to provide a driving connection between aconstant-speed source of power and a variable-load driven apparatus,which is capable of being so adjusted that the power delivered to thedriven apparatus is substantially proportional to the nominal loadencountered by that apparatus and even though the source of power is aconstant speed mechanism, such as a synchronous electric motor.

A further object is to provide a propelling mechanism for a variableload apparatus such that power may be delivered to such variable loadapparatus so as to avoid peaking the power input factor to theapparatus.

A further object is to provide a driving mechanism for a sprocket andchain drive of, for example, a drawbench, which may be so adjusted thatthe variable speed condition occasioned by the sprocket and chain driveis appreciably diminished.

A further object is to provide control means for a variable powerdelivery mechanism, such as a fluid drive, which causes the controlledparts of such mechanism to respond successively to two control devices,one of which is rendered effective as the other is rendered ineiiective.

A further object of the invention is to provide an improved drivingconnection between a source of power, such for example as a constantspeed motor, and a device subjected to various loads, such for exampleas a drawbench, which may be quickly controlled to effectively vary therate of application or the available power to the load in such a way asto minimize shock at the instant of initiating the application of suchpower to the load. 7

A further object is to provide simple and efiective driving mechanismfor the grip carrying device of a drawbench which includes a constantspeed motor, such as a synchronous electric motor, as the source ofpower and which is so arranged that the speed of the draw may be varied,within limits, and so that the draw may be so initiated as tosubstantially eliminate shock and then rapidly accelerated.

A further object is to provide a structure including a drawbench inwhich the motive power forthe drawing operation is delivered through theagency of a fluid drive and in which means are employed for controllingthe operation of the Iiuid drive by the movement of the carriage alongthe carriage ways of the drawbench.

A further object is to provide an operating mechanism for a drawbenchwhich includes a fluid drive and in which control mechanisms of thebench are employed for controlling the operation of the fluid drive.

An object of the invention is to provide a variable speed transmissionmechanism for the grip carrying device of a drawbench in which thesource of power is a synchronous electric motor and in which controlmeans are employed for adjusting such mechanism in anticipation of theload and at a timed interval prior to the imposition of the load so asto avoid undue shock at the imposition of the load and for thereafter soincreasing the power applied to the load as to rapidly accelerate suchgrip carrying device as it moves under load.

A further object is to provide a control mechanism for a fluid drivesuch that the scoop tube of the drive is so applied to the liquidannulus of the drive as to substantially avoid decreasing theeffectiveness of the annulus by creating undue turbulence and frothingtherein and which occasions a predetermined submergence of the scoop endof the tube within the annulus and then maintains the degree of suchsubmergence substantially constant under the changing condition of theannulus occasioned by the removal of liquid therefrom as a result ofsuch submergence.

These and other objects are attained by means of apparatus embodying thefeatures herein illustrated and described and by means of procedure suchas is herein defined.

In the drawings, accompanying andforming a part of my application,

Figure 1 is a diagrammatic, fragmental, side elevation of a unitarystructure constituting my invention and involving a drawbench and adrive mechanism therefor.

Figure 2 is a top plan view of a portion of the apparatus illustrated inFigure 1.

Figure 3 is an elevation of a portion of apparatus shown in Figures 1and 2 and a portion of such apparatus is shown in section along the line33 of Figure 2.

Figure 4 is a sectional elevation of a hydraulic coupling or fluid drive(parts being omitted for convenience of illustration), the section beingtaken along the line 44 of Figure 2.

Figure 5 is a diagrammatic side elevation of a portion of the apparatusillustrated in Figure 4.

Figure 6 is a fragmen-tal, sectional view along the line 6-43 of Figure3, diagrammatically illustrating a detail of my invention. Parts of theapparatus illustrated are transposed for clarity.

Figure 7 is a sectional elevation of a pressure control valveconstituting a detail of my invention.

Figure 8 is a sectional elevation of an adjustable pressure reducingvalve, such as may be employed in connection with apparatus embodying myinvention.

Figure 9 is a piping diagram, such as may be employed with. apparatusembodying my invention.

Figure 1G is a piping diagram, such as may be employed in connectionwith a modification cf the apparatus diagrammatically illustrated inFigure 9.

Figures 11 and 12 are each wiring diagrams.

Figures 13 to 20 inclusive and Figure 25 diagrammatically illustratesolenoid actuated contact devices or switches which are employed as apart of the electrical equipment constituting a detail of my invention.

Figures 21 to 24 inclusive are diagrammatic illustrations ofelectrically actuated valves illustrated in Figure together with theiractuating mechanisms which constitute details of the electricalequipment diagrammatically illustrated in Figure 12,

Figure 26 is a diagrammatic illustration of a portion of a powertransmitting chain and its driving sprocket.

Figure 27 is a curve which indicates the usual variations in power inputto a drawbench during a draw.

Figure 28 is a similar curve indicating improved power input conditionsoccasioned by the use of apparatus embodying my invention.

As illustrated in Figure l, a drawbench consists essentially of a frame,a carriage mounted on the frame, one or more drawing dies carried by thedraw head or die stand of the frame, means for moving the carriage alongthe frame away from the die stand to accomplish a draw and means formoving it toward the stand as a preliminary to a draw.

In the apparatus illustrated in Figure l, dies are carried by anupwardly projecting portion or die stand Ida which is shown as a part ofand located at one end of the frame of the drawbench. The dies 56 arepositioned above the ways I? along which a grip-carrying carriage i8 isadapted to move. A grip i9 is diagrammatically illustrated as carried bythe carriage at a point above the ways I! and so positioned that itsgripping jaws are in alignment with the dies l6. During a drawingoperation, one end of stock (bar or tube) to be drawn is insertedthrough the die [6 and its projecting end is gripped by the jaws of agrip Hi. When so gripped, it is drawn through the die by a move ment ofthe carriage away from the die. The die stand may be provided with oneor more dies and the carriage is provided with a separate grip alignedwith each such die and arranged to cooperate with it in the drawing ofstock.

The carriage [8 is moved along the ways l'i, throughout the drawingoperation, by means of a sprocket chain 22 and is adapted to beoperatively coupled to that chain by means of a hook 23, shown aspivotally secured to the carriage at a point approximately midway theends thereof, The hook 23 is normally held in its upper position asillustrated in Figure l by a latch 25, also pivotally secured to thecarriage, and sprin actuated to move into latching engagement with thehook. As shown, the latch 25 is actuated to release the hook 23 by a rod26. The rod is slidingly mounted on the carriage I8, is adapted toengage the die stand lBa as the carriage moves toward and into contactwith it, and is shifted, relatively to the carriage and longitudinallyof itself, by such engagement and thereby actuates the latch 25 torelease the hook. The release of the hook permits it to drop intocontact with the moving chain 22 and, by engaging a link of that chain,to operatively couple the carriage to the chain.

The elevation of the pivot point of the hook 23 is such that, after thehook is in engagement with the chain 22 and the chain is placed undertension by the drawing operation, the chain and hook will rise to such aposition that the hook is engaged by the latch and retained by it inelevated position. Under such conditions, the chain will beautomatically released from the hook and drop away from it-thus breakingthe operative connection between the carriage and the chain-when thetension on the chain ceases by reason of the stock leaving the die. Thelatch 25 will, however, retain the hook 23 in the elevated position, towhich it was raised by the pull of the chain 22, until the latch 25 isactuated by the rod 26.

After the carriage is operatively disconnected from the chain, its nextmovement will be toward the die stand 16a. This is accomplished by thegrip-return mechanism. As diagrammatically illustrated in Figure l, thegrip-return mechanism incluudes a motor driven sheave 30 on which acable 3! is reeved. The cable passes over sheaves 32 and 33 located atopposite ends of the frame and the opposite. ends of the cable are shownsecured to an extension 24 of the carriage 38, The sheave 30 is sodriven that it normally propels the carriage toward the stand 6a. It isalso so driven that its driving mechanism slips under excess torque,with the result that the carriage automatically stops as it abuts thestand I602, and is at least momentarily held against the stand 16a bythe grip-return mechanism.

As indicated, the grip-return mechanism is operated independently of thedraw chain 22, except that its operation, like the operation of the drawchain, is in part controlled by the movement of the carriage [8.

The draw chain 22 is operatively coupled to the runner 35 of a fluiddrive 36 by means of a shaft 35. The fluid drive mechanism isdiagrammatically illustrated inv Figures 4 and 5 and includes animpeller 31, mounted on a shaft 31', and located in co-operativerelation with the runner 35. The runner and the impeller are enclosed bya casing 31a which is carried by the drive shaft 37 but is so arranged,with relation to the runner 35, that the runner is capable of turningfreely of it and also of the impeller 37.

In the type of fluid drive illustrated, both the runner and the impellerare provided with radially extending vanes and the relationship is suchthat power is transmitted from the shaft 31' to the shaft 35 or from theimpeller 3'! to the runner 35 by means of liquid, which is delivered tothe interior of the casing 31a. That is to say, the fluid coupling isrendered effective, as a power transmitting device, by the delivery ofliquid (such as oil) to the chamber enclosed by runner 35 and impeller37 and in which the vanes of both are located. This chamber is sometimesreferred to herein as the power chamber. The degree of the couplingseffectiveness, as a power transmitting device, varies with the amount ofliquid within the power chamber. The runner 35 and impeller 37 rotate atthe same or substan-' tially the same speed when the casing 31a issubstantially full of power transmitting liquid (oil) and the couplingis then most effective as a power transmitting agent,

It is noted that the fluid drive illustrated is a well-known commercialtype of fluid coupling and, for that reason, the minute structuraldetails of the same are neither disclosed nor described. In the typeillustrated, the operating or power transmitting liquid is delivered tothe interior of the casing 31:: by means of a scoop tube 38. As shown,the scoop tube is located within a rotating cover 39 which, in effect,constitutes a rotating reservoir for the operating liquid delivered bythe tube to the power chamber enclosed by the impeller and the runner.The cover 39 is supported by the drive shaft 31' and consequently isrotated at the speed of rotation of that shaft and of the impeller 31,with the result that the liquid contained therein forms. undercentrifugal force, a liquid annulus which is located within an annularrecess 40, formed around and within the cover 39.

In Figure 5, the dot-dash circumference of a circle illustrates theextent of the liquid annulus under conditions such as obtain while allof the power liquid is retained within the annulus. As shown by dottedlines in Figure 5, the scoop tube 38 is capable of being moved aroundits pivotal support to diiferent positions so that its outer end orscoop is capable of occupying different positions with relation to theliquid annulus within the recess Ml of the cover 39. The scoop tube isthere shown in three positions. One in which the scoop end of the tubeis wholly removed from the liquid annulus; one in which the tube is soextended that the scoop end thereof projects into the annulus; and, onein which the tube is full extended and the scoop end thereof occupies aposition adjacent the inner periphery face of the recess 40. Suchmovements of the scoop tube 38 are accomplished by a control lever t I.

As the scoop end of the tube 38 enters the moving liquid annulus, theliquid is forced, by its rotative movement, through the tube andcommunicating passages and into the power chamber enclosed by theimpeller 31 and runner 35 and in which the vanes of both are located. Aspreviously noted, the eflectiveness of the fluid coupling depends uponthe amount of liquid within the power chamber and, in the scoop tubecontrol type of fluid coupling, the amount of liquid delivered to thatchamber is controlled by the position of the scoop end of the tube withrelation to the annulus of liquid within therecess 48 of the thenrotating reservoir 39.

The casing 31a is provided with a series of leak-01f ports 42, which arespaced around it and establish communication between the interior ofthat casing (i. e., the power chamber) and the interior of the reservoir39. Under such conditions, liquid delivered from the reservoir 39 to theinterior of the power chamber is continually leaking back into thereservoir, thus tending to empty the power chamber or casing 37a ofliquid and to break the operative connection between the impeller 3i andthe runner 35. It is for this reason that a continuous supply of liquidmust be delivered to the casing 31a in order to render the couplingeffective. The presence of the leak-off ports 42 also makes it apparentthat theposition of the scoop tube 33, with relation to the liquidannulus within the cover 39, measures the effectiveness-of the fluidcoupling as a power transmitting mechanism. That is to say, theeffectiveness of the coupling is controlled by moving the scoop end ofthe tube 38 to different positions with relation to the rotating liquidannulus.

The power liquid, which is stored in the form of an annulus withintherotating reservoir 39, is passed through a coolerduring the cycle ofits movement from one place to another. I, however, have not attemptedto illustrate the cooler or the passages leading thereto and therefromsince commercial fluid couplings are usually equipped with coolers andother structural de-v tails which ensure their effective operation.

The shaft 3'! may be operatively coupled to any. prime mover, such as anelectric motor, a steam engine, a turbine, or internal combustionengine. In the present embodiment, the use of the fluid coupling makesit possible to employ a constant speed prime mover, such as asynchronous electric motor, asthe source of power forthe drawbench, i.e., the power source for actuating the draw head of the bench duringdrawing operations. The shaft 35f is operatively coupled to the drivingsprocket l5 of the draw chain 22. The shaft 31' is shown in Figure 2 asoperatively connected to a synchronous electric motor it.

In the apparatus illustrated, a drawing operation is initiated by amanually actuated control and the further operations are then capable ofbeing carried forward automatically. Assuming that a draw has beencompleted, that the carriage it occupies a position along the ways I!remote from the die stand lBa and that the drawn stock has been removedfrom the grips and from the machine, the next step is to prepare foranother draw. Under conditions assumed, the initiation of the drawingoperation will start the carriage 18 moving toward the die stand Ilia.This is accomplished by grip-return mechanism and the arrangement issuch that the carriage first moves at a relatively high speed toward thedie stand [6a and, after it reaches a predetermined or selected point inits return travel, its speed is checked so that it then moves slowly toits final position adjacent the stand Ilia where the grips engage thestock to be drawn.

The starting of the grip-return mechanism is accomplished by means of amanually actuated control and, in the apparatus illustrated, the controlis a push button forming a part of an electrical control system. Theinitial return speed of the grip-return mechanism is reduced by a limitswitch A, which is carried by the frame of the drawbench and ispreferably adjustable to different positions along the line of travel ofthe carriage It. The control deviceA is adapted to be actuated by anextension or cam secured to the carriage and so positioned that it isalso capable of actuating a second limit switch or control device B alsocarried by the frame of the bench and also preferably'adjustable todifferent positions along the path of travel of the-carriage It. Theextension or cam for actuating the control devices A and B may beindicated by the extension 24 to which the ends of the grip-return cableM are shown secured. This extension will be hereafter referred to as thecam 24.

. The first control device A checks the speed of the grip-returnmechanism by means of apparatus, not here illustrated andiorming nopartof the present invention, except that it does accomplish a checking ofthe speed of the gripreturn mechanism. The second control deidce B alsoexercises a controlling function on the operation of the grip-returnmechanism but, here again, the instrumentalities for accomplishing thisare not illustrated. These control devices A and B are, however,important to the present invention because they co-operate with othermechanisms in accomplishing an automatic control of the drawbench and ofthe fluid coupling 36, which motivates the draw chain 22 and constitutesthe effective source of power during the drawing operation.

In the apparatus illustrated, the impeller 37 of the fluid coupling isdriven continuously by means of the motor 45, although the draw chain 2?is only driven during and immediately pre-' ceding a draw. The operationof the draw chain is controlled by the scoop tube 38 consequently, theautomatic positioning of the scoop tube and the mechanisms foraccomplishing such positioning form an important part of my invention.

In accordance with my invention, the fluid coupling 35 is so controlledthat the draw chain is accelerated to what may be termed hookm speed, i.e., a speed at which the carriage it can be efiectively coupled to thechain without subjecting the apparatus to undue shock or impact strainsbut, at the same time, a speed which is sufileient to initiate thedrawing operation. The draw may be initiated as the speed of the 22 isaccelerating to draw speed and the acceleration may then be continuedthroughout the draw or until the desired dra Y speed is attained.

The completion of the draw and the resultant lessening of the load onthe draw chain 22 not only breaks the connection between the chain andthe carriage I8, by releasing the chain from the hook 23, but it alsooccasions an automatic withdrawal of the scoop tube 33 from the liquidannulus within the rotating reservoir 39 and thus renders the fluidcoupling 26 ineffective by breaking the driving connection between theimpeller 31 and the runner 35, i. e., by breaking the operatingconnection between the drive shaft 3'! and the driven shaft 35.

Apparatus is illustrated in Figure which, in co-cperation with'otherdevices, accomplishes a rapid extension of the scoop tube 33 in theoperation of partially filling the power chamber within the casing 33aas a preliminary to initiating a drawing operation. By employing theapparatus there illustrated, the fully withdrawn scoop tube may berapidly moved to an extended position under the control of one deviceand at a rate which, if continued, would rapidly extend the tube to itsextreme position. The operation of the apparatus is, however, such thatduring this rapid movement of the tube in response to the control of onedevice, the control is shifted to another device with the result thatthe second device positions the tube, with relation to the liquidannulus within the rotating covers 35- and thus designates the degree ofeffectiveness of the fluid coupling as a power transmitting device bycontrolling the extent to which the power chamber within the casing 31ais filled with liquid. The second device designates the position of thescoop tube and independently of the position to which it has moved whenthe second device hecomes efiective as the control device.Simultaneously with the initiation of the rapid movement or the scooptube, under the control of one device, the second control device is setfor subsequently controlling the positioning of the tube. This seconddevice, if acting alone, would occasion a slower movement of the scooptube and a movement to some selected point of extension only, with theresult that the power chamber of the casing 31a would be much moreslowly filled, to the selected degree, with power transmitting liquid.Prior to the time that the scoop tube is totally extended, theinstrumentality then controlling its movement is rendered ineiiectivewith the result that the tube responds to the control of the seconddevice.

The control lever ll of the scoop tube is actuated by a motor 41 whichis diagrammatically illustrated in Figures 3, 6, 9 and 10. Asillustrated, the motor Ill is a diaphragm motor, is provided with apower-actuated lever 8 and is associated with a pilot valve mechanism,structural details of which are diagrammatically illustrated in Figure6. The motor 4's is provided with a casing 69" which constitutes asupport for a diaphragm i5 and housing for a coiled spring 51 and adiaphragm-actuated link 52, which is pivotally connected to the lever33. As shown in Figures 3 and 6, the cover ill of the casing engages theedge of the diaphragm and with the diaphragm provides a pressure chamberdid to which fluid pressure is delivered for the purpose of actuatingthe diaphragm. In the illustrated embodiment, the cover is provided withtwo ports 58' and Sta, each of which opens into the chamber Lila. Theport 56' communicates with piping 53 and the port 50a communicates withashort length of pipe 5 The piping 5d communicates with a manifold '55to which fluid under pressure is adapted to be delivered through piping5? and which is provided with a supply port 57 controlled by a valve 58,located within the manifold and capable of being actuated by a beam 59.

The apparatus illustrated in Figure 6 is 3. diagrammatic simplificationof a commercial type of pilot control mechanism for controlling theposition of the diaphragm 49, and consequently the position of the lever38, in response to the pressure of the fluid delivered to the manifold55 through the piping 51'. As illustrated in Figure 6, the beam 59approximates a walking beam and is supported by links 60 and Bi. Thelink 53 engages and is supported by the diaphragm t9 and the link 8|engages and is supported by a pressure responsive device 62 illustratedas a form of sylphon bellows. Each of the links 60 and BI is pivotallysecured to the beam 59 and the bellows G2 is located within a pressurechamber 62a of the manifold 55 and is so arranged that its exterior isexposed to the pressure existing within that chamber, whereas itsinterior is open to the atmosphere. Under such conditions, one end ofthe beam as will move up and down in response to the variations inpressure delivered to the chamber 62a, whereas the other end will movewith the diaphragm li A coiled spring 5 is shown as operating betweenthe beam 59 and the casing of the manifold 55 so as to tend to move thebeam downward against such lifting force as may be applied thereto byeither or both of the links iiil-Gi. The spring 64 contributes to theopening of the supply valve 58 as either or both of the links '3!) and6! move upwardly.

The link 60 projects through the port 59a, the pipe 54, the passage 63and a gasket 55. The

9 passage 63 is formed within the manifold, with its lower end in opencommunication with the port 58a and its upper end communicating with apassage 63' also shown as formed within the manifold and adapted tocommunicate with the port 51 when the supply valve 58 is open. Thus thesupply port delivers fluid under pressure to the chamber 41a through theport 50a of the diaphragm motor l when the supply valve 58 is open. Thesupply valve is normally seated but an upward movement of the beam 59,acting through the coiled spring 64 and valve stem 58 raises it and thusplaces the supply port 57 in communication with passage 53 and deliversfluid under pressure to the chamber lla.

Exhausting the fluid from above the chamber 57a causes the spring 5! toraise the diaphragm t9 and, consequently, the link 60 and one end of thebeam 59, and, depending on the position of the link 5|, will open thesupply valve 58. That is to say, the supply valve responds to therelative positions of the two end of the beam 59 or the relativepositions of the diaphragm 49 and the bellows 62. Under such conditions,the diaphragm d9 will occupy a definite and predetermined position foreach different fluid pressure delivered to, and maintained within thechamber 52a of the manifold 55.

The piping 53 is shown in Figure 10 as communicating with a source offluid pressure, such as an adjustable pressure regulator valve 53',which is of more or less usual construction and is diagrammaticallyillustrated in Figure 8. The pipe 58 constitutes a branch pipe andextends between the chamber 62a of the manifold 55 and the pipe 53. Itcommunicates with the pipe 53 at a point such that the inlet end thereofis in open communication with the source of regulated pressure, i. e.,with the delivery port of the pressure regulator valve 53. This pipe 56includes a three-way valve VI, a three-way valve V2 and a pressureadjusting device 65, known commercially as a grad-U-switch (seeMinneapolis Honeywell Regulator Company Bulletin, Bulletin 95-984A).

As illustrated in Figure 10, one position of the valve Vi establishescommunication between the chamber 82a of the manifold 55 and an exhaustpipe 66. The valve is, however, capable of being turned so as to shutoil communication with the exhaust pipe 66 and to establishcommunication with the valve V2 so as to place the delivery port of thedevice 65 in communication with the chamber 62a of the manifold 55. Thevalve V2 is shown in Figure 10 as establishing communication between thepiping 56 and branch piping 61. The branch piping 61 also communicateswith the piping 53 at a point such as to receive the fluid pressuredelivered by the'pressure regulator 53' and it is also provided with apressure adjust ing device 65' similar to the grad-U-switch 65. Thedevice 65, like the device 65, is capable of being adjusted to deliverand maintain a predetermined pressure below that of the source of fluidpressure. The device 65 is in all respects similar to the device 65' andis diagrammatically illustrated in detail in Figure 7.

As shown in Figure 7, fluid is delivered to the interior chamber of thedevice 65 by what may be termed an inlet valve 68 which is normallyseated by a coiled spring and the pressure of the fluid at the inletport of the device and which is controlled by a pressure responsivediaphragm 69 through the agency of a stem 69a and-lever 69'. Thedevice-is-also provided with a discharge valve 68 which is normallyheld-to its seat by a coiled spring and which responds to the movementof the diaphragm 69, being actuated by stem 65a and a lever 59". Thediaphragm G9 is exposed on one side to the fluid pressure within thedevice and on the other side to atmospheric pressure and the pressure ofan adjustable spring Hi. The spring 10 is provided with an adjustablespring seat and this is positioned by means of a cam ll capable of beingturned to different positions by a hand lever Tl, illustrated in Figure10.

The piping 53 (Fig. 10) is interrupted by a valve V3 and communicateswith an exhaust pipe l3 which is provided with a valve V4. The valve V3is intermediate the source of pressure (pressure regulator 53') and theexhaust pipe 13 and is adapted to close off communication between thesource of pressure and the pressure chamber of the diaphragm motor 47when turned to'the position indicated in Figure 10. When turned aquarter turn from that position, it establishes communication betweenthe source of pressure and the diaphragm motor. The valve V4 is adaptedto be turned to either establish or close oii communication between thepiping 53 and the exhaust pipe 13. In the position indicated in Figure10, the exhaust pipe is, in effect, closed. A quarter turn of the valveV4 will, however, establish communication between the pipe 53 and-theexhauts pipe 13 and exhaust the pressure from the chamber above thediaphragm 49 of the motor ll.

The valve V2 is adapted to establish communication between the chamber52a of the manifold 55 and the delivery port of one or the other of thedevices 65 and 65'. In the position indicated in Figure 10, itestablishes communication between the chamber 62a and the device 55(assuming the valve VI is turned a quarter turn counterclockwise) but bybeing turned a quarter turn counter-clockwise, communication between thedevice 65 is cutofi and communication is established between the device55 and the chamber 62a in which the bellows 62 are located. 1

As shown in Figure 6, the manifold 55 is provided with a small leak-offport l5 which communicates with the passage 63' and consequently withthe pressure chamber d'ia above the diaphragm d9 'of the motor 47. Thisleak-oil port is shown as a passage surrounding the stem 58' of thesupply valve 58 and communicating with the passages 63' at a pointimmediately above the disk of the valve 58. With such an arrangement,fluid under pressure can onlybe maintained in the pressure chamber 41awhile that chamber is in communication with asource of high pressurefluid, either through the port 5!! or the port 55a as illustrated inFigure 6.

It will be apparent from Figure 10 that the valve V3, when open,delivers fluid under pressure direct from the pressure regulator 53 tothe chamber 41a of motor 41 and causes the dia-'- phragm 49, and themechanisms actuated by it, to move in response to the pressure'sodelivered. It will also be apparent that a positioning of the valve V4,to place the piping 53 in communication with the exhaust pipe 13, willexhaust the pressure chamber 41a (if the valve V3 is closed). Thepassages and ports directly communicating with the valves V3 and V4 maybeso proportioned that the opening of the valve V3 occasions arelatively rapid delivery of fluid under pressure to the chamber 41a andan opening of the valve V5, causes a rapid exhausting of that chamber.It will also bejapparent that opening either of the valves V3 or V4 (theother being closed). will have the effect of taking the control of thediaphragm motor 4'! away from the pilot mechanism, i.e., the mechanismwhich includes the piping 56, the valves VI and V2, the grad-U-switchesE and E5 and the chamber 62a of the manifold 55. It will also beapparent that the valve V2 may be turned to render either the pressureadjusting device 65 or 65 effective, in controlling the positioning ofthe diaphragm is, when the valve Vi is positioned to close the exhaustport 65 and both the valves V3 and vs are closed. Likewise a shifting ofthe valve Vi to place the chamber 620: of the manifold 55 incommunication with the exhaust pipe 65 will render both devices 65 and65' ineffective as control mechanisms for the motor ll.

From the foregoing, it will be apparent that the apparatusdiagrammatically illustrated in Figure may be employed in controllingthe positioning of the scoop tube 38 and that it may be so employed asto move and hold the tube in any one of four selected positions, via, aposition in which the tube is wholly withdrawn from the liquid annulus;one in which the tube responds to the control of the device 65' and thescoop end thereof is partially submerged by the liquid annulus; one inwhich the tube responds to the control of the device 65, is furtherextended and occupies a posi tion, with relation to the annulus, such aswill maintain an amount of liquid within the power chamber of the casing37a essential for drawing operations; and, one in which the tube isfully extended.

When the valves VI V2, V3 and V 4 are all in the positions shown inFigure 10, the scoop tube will occupy the first mentioned positionbecause the chamber 62a is open to the atmosphere through valve Vi andpipe 65 and the upper face of the diaphragm G9 is subjected toatmospheric pressure, the leak-off port being open and all fluiddelivery valves being closed. Under such conditions, the link GB ismoved to its uppermost position by the diaphragm 39 and the link 6! ismoved to its lowermost position by the bellows E2 and the beam 59occupies a position in which the supply valve 58 is closed.

Now assume that the device $5 is adjusted to deliver fluid from thesource 53 at a relatively low pressure and the valve Vi is given aquarter turn counter-clockwise. Under such conditions, the

bellows G2, responding to the fluid pressure so delivered to the chamber62a, will partially contract, lifting the link 8i and moving the beam 59about its pivotal connection with link 63. This will open the supplyvalve 58 and thereby deliver fluid under pressure from the source 53' tothe chamber 41a above the diaphragm 49. The diaphragm, movingdownwardly, in response to the pressure so delivered, will shift theposition of the beam 59 around its pivotal connection with the link 6!and will close the valve 58 after reaching a predetermined position.Thus, it is apparent that the position of the diaphragm 49, at which thevalve 58 is closed, will depend upon the position of the link 6| or thedegree of fluid pressure acting on the bellows 62. In other words, thediaphragm 49 will move downwardly until the supply valve closes and thismovement will move the tube 33 to the second position.

If it is now assumed that the device 55 is adjusted to supply fluid fromthe source 53 at a somewhat higher pressure than it is supplied from thedevice 65 and that the valve V2 is turned a quarter turncounter-clockwise, then, the chamber 62a will be subjectedto thepressure of the fluid delivered by the device 65. The bellows 82,responding to the increasing pressure, will raise the link El therebylifting the beam 59 around its point of connection with the link 50 andwill open the supply valve 53. Fluid under pressure will then bedelivered by the supply valve 58 to the chamber ita and that valve willremain open until the diaphragm L 9, moving in response to the pressurewithin the chamber 41a, again shifts the position of the beam 59sufficiently to close it. This movement of the diaphragm will move thetube 38 to the third of its above mentioned positions. If the lever l iis turned counter-clockwise to its extreme position, the pressuredelivered to chamber 62c would be such as to move the tube to the fullyextended or fourth of the above mentioned positions.

In view of the fact that the leak-off port I5 (Fig. 6) is continuallyopen, it will be apparent that, as soon as the diaphragm it! moves to aposition such that the valve it closes, its further movement will bearrested and the leakingoif of fluid from the chamber ile will cause itto momentarily lift and open the valve 58, thus occasioning a momentarydownward movement of the diaphragm and a closing of the supply valve. Inother words, the diaphragm will hunt (pulsate) but will generallymaintain the position designated by the position of the link Bl or thedegree of fluid pressure delivered to the chamber 52a.

The fourth or fully extended position of the coop tube 33 also beattained by opening the valve V3 and maintaining it open a sufiicienttime to enable the diaphragm 49 to move to its lowermost position. Aswill be disclosed by the further description of the apparatus, the tubeEli never fully extend while responding to the automatic operation ofthe apparatus illustrated, although its final position will alwaysdepend on the forces acting on the diaphragm 49 of the motor ill. It,however, should be noted that the device '85 may be so adjusted as toeither partially or fully extend the scoop tube 38 during automaticoperation and, therefore, during a draw.

A reference to Figure 3 will disclose that the power lever .8 isoperatively connected to the scoop tube actuating lever 41 by means oflink 16, lever ll, shaft 73, lever ES and link 88. The power lever 48,the actuating lever 48 and the other parts of the motion multiplyingmechanism are shown in full lines in the positions such that the scooptube 33 is fully withdrawn from the liquid annulus or occupies the firstabove mentioned position. A stop 8| is carried by the frame of theapparatus and, by engaging the lever 19, limits the throw of the powerlever =8 and thus designates the position occupied by that lever whenthe scoop tube 38 is fully extended or occupies the fourth of the abovementioned positions. The power lever 48, the lever ti and theintermediate parts of the motion multiplying mechanism are shown in theextreme position by the dot-dash lines of Figure 3.

The arrow of Figure 5 designates the direction of rotation of the cover39 and, consequently, the direction of movement of the liquid annulus.The liquid of the annulus, therefore, resists extension of the scooptube and on being penetrated tends to move the tube out of contact withit. The resistance ofifered by the liquid is substantial because thecover 39 is rotating at a relatively high speed. The resistance topenetration by the scoop tube also increases as the degree ofpenetration increases. On the other hand, the quantity of liquid in theannulus decreases as 13 the scoop tube transfers liquid therefromto thepower chamber within the casing 31a (Figure 4) of the fluid coupling.The resulting'change in the liquid annulus contributes to the extensionof the scoop tube, although the resistance to penetration by the tubedoes not decrease.

The effectiveness of the fluid coupling, as a power transmitting device,increases as the power chamber fills with liquid from the annulus. Itis, therefore, desirable to fill the power chamber rapidly in order toconserve time in connection with the operationof the apparatus to whichthe power is transmitted by the coupling. On the other hand, it isdesirable to so actuate the scoop tube that it penetrates the annuluswithout destroying its effectiveness by creating undue turbulencetherein and a resulting frothing of the liquid. For this reason, theactuating fluid is delivered to the pressure chamber 41a above thediaphragm 49 (Figure 6) at a pressure which will cause the scoop tube topenetrate the annulus as rapidly as possible without destroying theeffectiveness of the annulus. I also shift the control from one deviceto another, as described in connection with Figures 10 and 12, in orderto speed the drawing operations of the drawbench.

As to this control, it will be noted that more rapid extension of thescoop tube will be accomplished in response to actuating fluid delivereddirectly to the chamber 41a through the piping 53 than is capable ofbeing accomplished by delivering the actuating fluid through the piping51', the supply valve 58 and the manifold connections, in response tothe control of one or the other of the devices 65 or 65', although ineach case the scoop end of the tube is applied to the liquid annulusunder substantially the same conditions. The reason for the differencein the rate of tube extension is that the fluid pressure, delivered tothe chamber 41a directly through the piping 53, is fully elfective inmoving the diaphragm 49 (and, consequently, in extending the scoop tube)up until the closing of the valve V3, whereas the movement of thediaphragm 49, oocasioned by the delivery of actuating fluid through theupply valve 58, results in a gradual closing of the supply valve as thediaphragm 49 approaches the position designated by the then effectivecontrol device (65 or 65). I, therefore, prefer to rapidly extend thescoop tube, and to over-extend it, by delivering actuating fluid throughthe piping 53 directly to the chamber 47a and then to position the tubeunder the control of one or the other of the devices 65 or 65, after thevalve V3 is closed.

In the further description of the operation of the scoop tube, it shouldbe borne in mind that an appreciable time (approximately 10 seconds) isconsumed in filling the power chamber of the fluid coupling to theextent essential for accomplishing a draw at the desired rate. As tothis, it will be recalled that the dischargev or leak-off ports 52 of.the power chamber (Figure 4) are continually open and that, therefore,a balanced condition is obtained as between the amount of liquid in theannulus and the extent to which the power chamber of the coupling isfilled by holding the scoop tube in a fixed extended position and that,the degree to which the power chamber is filled and, consequently, thedegree of effectiveness of the fluid coupling as a power transmittingdevice, will be varied by varying the position of the scoop tube withrelation to the annulus.

It will'also be noted that, under conditions d scribed in connectionwith Figures 10 and 12, the force involved in accomplishing an extensionof the tube 38 also-accomplishes a predetermined submergence of thescoop end of the tube in the liquid of the annulus and then maintainsthat degree of submergence substantially constant as the extension ofthe tube continues in response to the changing condition within theannulus occasioned by the removal of liquid therefrom by the scoop tubein its function of delivering liquid to the power chamber.

In Figure 12, I have shown a wiring diagram which diagrammaticallyillustrates an electrical system employed for controlling the operationof the drawbench throughout the entire cycle of initiating andcompleting a draw. For the purpose of simplifying the wiring diagram,certain of the devices indicated in the diagram are more fully, althoughdiagrammatically, illustrated in Figures 21 to 24 inclusive of thedrawings. As to these figures-it is noted that Figures 21, 22, 23 and 24are respectively diagrammatic illustrations of the valves VI, V2, V3 andV9, each being shown in connection with a diagrammatic illustration ofits actuating devices. Throughout that portion of the description whichbears on the wiring diagram of Figure 12, reference will be made to theappropriate figures (Figures 21 to 24) so as to amplify the disclosureof the wiring diagram.

Assume that a draw has been completed; that the carriage I8 is remotefrom the die stand 56a; and, that it is desired to start the cycle ofthe drawbench for the purpose of initiating and completing a furtherdrawing operation. This is accomplished by momentarily depressing thegrip-return switch, shown in Figure 12 as a push button type of switchC, so as'to break the connection between leads x1 and x8 and establishelectrical connection between leads xl3 and xl4, thus completing thecircuit X, xl3, switch C, xld, x15, solenoid D, will, mil, contact Ea,forming a part of the contact device E, :rl8 and Y.

It should be noted that the motor M, which is the driving motor 46operatively connected to drive shaft 3'! of the coupling 36, isoperating under minimum or idling load conditions and that the minimumload input of current traverses the circuit X, ml, motor M, 1:2,solenoid H of the contact device H, $3 and Y but is not suiflcient toenergize the solenoid H to operate the contact device -I-I. Energizingthe solenoid D actuates the contact device D and moves the contact Do toestablish the circuit X, 3226, contact Ba of the switch device B, 9321,contact Do, .1228, 2e29, :L'ZI, :cl5, solenoid D, $16, mil, contact Eaof the contact device E, m8 and Y, thus establishing a holding circuitfor the solenoid D. Momentarily depressing the switch C (grip-returnswitch) also starts the operating motor of the grip-return mechanism andunder conditions such that it moves the carriage [8 at full speed towardthe die stand lBa. The circuit for accomplishing this is not shown,forming no part of the present invention. This full speedv movement ofthe carriage l8 continues until the cam 2d depresses the contact deviceA (Fig. 1), which not only reduces the speed of the grip-return motorand consequently of the carriage l8 but also establishes the circuit X,.126, Ba, .7321, Da, r28, r29,

ing the solenoid. V2 being energized, and also renders contact Fa.effective thus establishing the circuit X, x26, contact Ba, 5021,contact Ba, 0228, a130, contact Fa, 203i, r45, r51, m ld, solenoid V3,$49, contact Go of timerelay device G (Fig. 2G) x50 and Y, thus causingthe valve V3 to move a quarter turn counter-clockwise from the positionshown in Figure and deliver fluid pressure to the diaphragm motor d'lthrough the piping .53 and direct from the pressure source (pressureregulator 53'). This, in turn, actuates the lever 58 and underconditions such that the scoop tube 35 moves at a maximum rate and tendsto completely fill the power chamber 37a of the fluid coupling 35.

Closing the contact Fa also establishes the en'- cuit X, r28, contactBa, 3027, contact Dc, r28, 3338, contact Fa, 3:31, 1:33, solenoid Vi9:355 and Y, thus causing the valve VI to move a quarter turncounter-clockwise from the position shown in Figure 10 and, in that way,place the. chamber 62a in communication with the device 65 through thevalve V2, the valve Vi, the branch piping. 5%. This causes the bellows6?. to move in response to the pressure delivered by device 85' toposition the link iii in what has been termed the second selectedposition. This sets apparatus so that fluid pressure, as adjusted by thedevice t5, will be effective in controlling the position of the lever 46and, consequently, the scoop tube 38 after the valve V3 is closed.should be noted that the carriage l8fis still moving toward the diestand lEicL, thatthe hook 23 is held out of.

contact with the draw chain 22 by the latch 25,

and that consequently moving the scoop tube 38.

the circuit X, r26, contact Ba, 3127, contact Dc,

$28, $39, contactFa, 203i, w ld, x45, solenoid G of the time relaydevice G, x ii: and Y. Energizing the solenoid G will, after a brieftime interval, move contact Go of the time relay G and break the.electrical connection between 39 and $59 thereby opening the energizingcircuit of solenoid V3.

The delayed action of the solenoid G is occasioned by the'dashpotmechanism G1) which is diagrammatically illustrated in Figure 12 andwhich delays the action of the solenoid G for a definite period (a fewseconds) after the solenoid is energized. Dre-energizing the solenoid V3results in an iinediate closing of the valve V3 and this places thecontrol or" the diaphrgam motor ll on the device 65', the valve Vl beingturned a quarter turn counter-clockwise from the position shown inFigure 10. As previously pointed out, the pressure chamber above thediaphragm cc of the motor or, is always in comunication with a leak-offport 15' consequently the excess pres sure, delivered through the valveV3, is dissipated and the diaphragm 49, therefore, responds to thepressure of the fluid deliveredthrough the supply valve 51 and thepassages of the manifold 55 after the valve V3 is closed. That is tosay, if the scoop tube 33 has been over-extended it will move back asthe diaphragm "59 (Fig. 6) adjusts its position to correspond to thepressure delivered by the device 65,.

The carriage I8 'is continuing its movement toward the die stand its,although at a slow speed, and the cam 2d depresses the switch mechanismB This actuates contact Ba to breal; electrical contact-between thewires 0:26 andzcZ'i and renders the contact Bb effective in establishingthe circuit X, 0235, contact Bl), r36, r31, solenoid E, x38 and Y thusenergizing the solenoid E and actuating the device E to break electricalconnection between the wires mi! and :rl8 and render the contact Ebeffective. The breaking of the circuit by opening the contact Ba,deenergizes the solenoids D, F, V! and G. The closing of contact Bbestablishes the circuit X, $35, no, 3338, 93 3i, 5642, contact Eb, $43,$47, $48, solenoid V3, w ll contact Ga, x and Y. The energizing of thesolenoid V3 again opens the valve V3 delivering maximum fluid pressureto the motor 47 and thus tending to over extend the scoop tube 38.

Closing the contact El) also establishes the circuit X, $35, B1), 2:36,2348, x42, contact 5Tb, $43, wi l, x33, solenoid Vl x34 and Y.Energizing the solenoid Vi turns the valve Vl a quarter turncounter-clockwise from the position shown in figure 10. Closing thecontact Eb also simultaneously establishes the circuit X, $35, no, 5036,ml, $42, contact Eb, 2:43, 114?, 325i, x52, solenoid V2 (Fig. 22), $53,contact Fb, x54, and Y. (Note that contact FE), Figure 17, is normallyclosed unless solenoid F is energized.) Energizing the solenoid V2 turnsthe valve V2 a quarter turn counter-clockwise from the position shown inFgure it) which closes off communication between the device and themanifold 55 and establishes communication between the device themanifold, the valve V! being open or in a position to close oilcommunication with the exhaust pipe 6E. The valves V1 and V2 are,therefore, so positioned that the motor 4'! will respond to the pressuredelivered by the device 8t as soon as the time relay G actstode-energize the solenoid V3 by breaking electrical contact between wiresx49 and roll.

Rendering the contact Eh eifective also establishesthe circuit X, $35,Bb, 9:36, 33M, zit-l2, contact Eb, 3743, x45, solenoid G, .1046 and Y.Energizing the solenoid G causes the time relay to operate and break theelectrical connection between wires 1:69 and 1258, after a brief timeinterval, thusde-energizing solenoid V3 and shutting off the delivery offluid through the piping 53 tothe diaphragm motor 41. This shifts thecontrol of that motor ll to the device 65 through the valves Vi and V2,the branch piping 56 and the manifold 55. Thus, the scoop tube isextended in response to fluid pressure delivered direct to the pressurechamber lla through piping 53, and then its position is adjusted underthe control of the device 85, which, in fact, designates the position ofthe diaphragm 19 at which the. supply valve 58 6) closes.

When all this has occurred the carriage [8 has moved slowly intoengagement with the die stand 1 6a. and the rod 26 has moved to releasethe hook 23' so that it drops into engagement with the chain 22 andoperatively couples the carriage l8 to the chain. The grips 19, carriedby the car riage, have also-engaged and gripped the stock projectingthrough the dies I6 as a preliminary movement of the carriage, so thatthe draw is l completed at a rate designated by the position assumed bythe scoop tube 38 under the control of the device 65. The time lag,encountered in filling of the power chamber of the coupling to thedesired extent contributes to the initiation of the draw at slow speedand, therefore, without undue shock or strain.

As the latch 25 is actuated to release the hook 23 and operativelyconnect the carriage I8 to the draw chain 22, the draw is initiated bythe carriage moving away from the die stand Ifia. As this movementcontinues, the cam 24 releases the contact B and current is shut ofi tothe motor driving the grip-return sheave SI! by mechanisms not shownwith the result that the drawing movement of the carriage I8 drives thegrip-return motor in a reverse direction through the agency of the cable3| and the sheave 30.

The load on the carriage increases the current input to the motor Mwhich, as noted, is operatively connected to the drive shaft 31 of thefluid coupling 36. The increased current input to the motor M energizesthe solenoid H of the contact device I-I establishing the circuit X,:039,

contact Ha, :c II], MI, 1131, solenoid E, 11:38 and Ythus establishing aholding circuit for the solenoid E and so maintaining the circuit lastdescribed after cam 24 releases the switch mechanism B and causes thecontact Bb to move out of electrical connection with wires x35 and x36.Energizing the solenoid II also moves contact Hb to break the electricconnection between $55 and x56 thus establishing a situation wherein thesolenoid V4 (Fig. 24) cannot be energized until the last mentionedelectrical connections are again established.

The energizing of solenoid H also moves the contact Hd to establish thecircuit X, $4, $5, contact Hd, m6, ml I, solenoid I of the contactdevice I, :vI2 and Y. Energizing the solenoid I closes contact Ib. This,however, has no eiTect on the energizing circuit of solenoid V4 becausecontact H1) is open. The energizing of the solenoid I also actuates thecontact Ia to establish the circuit X, :05, x1, switch C, :08, switch L,m9, contact Ia, all), :cI I, solenoid I, :rIZ and Y, thereby providing aholding circuit for the solenoid I.

When the carriage I8 has moved away from the die stand I6a to a pointsuch that the draw has been completed (the stock pulling out of thedie), it and the motor M are immediately relieved of the drawing loadwiththe result that the current input to the motor M immediatelydiminishes to the no load minimum and the solenoid H is no longereffectively energized. This actuates the contacts Ha and Hd,interrupting the electrical connection between wires m5 and m6 andbetween wires x39 and x40. De-energizing solenoid H causes contact Hb toestablish the circuit X, 31:55, contactHb, $56, contact Ib, :r5'I,solenoid V4, 958 and Y. Opening the contact I-Ia shuts off theenergizing current to the solenoids VI, E, G and V2 which results in anopening of the contact Eb and a shifting of the valves VI and V2 to thepositions shown in Figure 10. This not only shuts off the supply offluid pressure to the chamber 62a of the manifold but it alsoestablishes communication between that chamber and the atmospherethroughthe pipe 56, the valve VI and the pipe 66. As a result of this, the beam59, moving in response to the equalizing of pressure on the interior andexterior of the bellows 62, occasions a closing of the supply valve 58(Fig. 6) thus shutting ofi the supply of fluid pressureto the pressurechamber 41a above the diaphragm 49 of the motor 41. Energizing thesolenoid V4 (Fig. 24) shifts the valve V4 a quarter turn from theposition shown in Figure 10 thus establishing direct communicationbetween the pressure chamber 41a and the exhaust pipe 13 through themedium of the pipe 53 and the valve V I. This accomplishes an immediateexhausting of the pressure chamber 41a. The solenoid V3 is not energizedand consequently the valve V3 is closed.

As a result of all this, the diaphragm 49 (Fig. 6) moves to itsuppermost position (in response to pressure of spring'SI) and therebytotally retracts the scoop tube 38, i. e., withdraws it from the annulusof liquid within the rotating reservoir 38. This-cuts off the supply ofliquid to the casing 31a (Fig. 4) with the result that the leak-on"ports 42 empty that casing and, therefore, are efiective in breaking theoperative connection between the impeller 31 and the runner 35 or theoperative connection between the drive shaft 3'! and the driven shaft35. say, the driving connection between the motor M (45) and the drawchain 22 is broken with the result that the chain 22 ceases to move thecarriage I8 and the motor M runs idle, i. e., under minimum loadconditions. Unloading the chain 22 causes it to drop away from the hook23 which, as previously noted, was moved into latching engagement withthe latch 25 (Fig. 1) as the drawing load caused the chain to straightenout or rise and thus lift the hook 23 with it and into engagement withthe latch.

With the various parts of the apparatus in the positions last described,a momentary closing of the push button switch 0 will break the circuitX, m4, m1, switch 0, x8, switch L, m9, contact Ia, :cIII, :cI I,solenoid I, a:l2 and Y thus deenergizing solenoid I and opening contact1b, thereby de-energizing solenoid V4. This will close the valve V4 orclose off communication between the piping 53 and the exhaust pipe I3.The momentary depression of the switch C will also close a circuit (notshown) for delivering current to the driving motor of the grip-returnmechanism and, therefore, will initiate a return movement of thecarriage I8. The momentarily depressed button C will alsoestablish thecircuit X, xI3, contact C, mI I, :z:l5, solenoid D, .rIB, xl'l,

- contact Ea, :vIB and Y and thus initiate the cycle of the drawbenchwhich has just been described. Ihe push button switch J,diagrammatically illustrated in Figure 12, may be termed the draw resetswitch. When depressed, it establishes the circuit X, x59,'contact- J,.7369, :c-il,

$31, solenoid E", x38 and Y. Energizing thesolenoid E initiates all theoperational steps previously described as ensuing therefrom during theautomatic operation of the drawbench while the hook 23 is in engagementwith the chain 22 and the grips 9 are drawing stock through the dies I6.The switch J, therefore, provides manual means for initiating allautomatic operations describedas resulting from the automatic actua-'tion of the control device B to render the contact Bb effective as apart of'a current delivering circuit.

The switch K, shown in the form of a push button in the diagram ofFigure 12, may be termed the hook-in reset switch. Depressing the switchK closes the circuit X, :rI-II, switch K, 2262, :c5l, 3:41, $44, a232,5024, solenoid F, x25,

.rI'I, contact Ea, a2I8 and Y. Energizing the solenoid F initiatestheseries of operations previously described as ensuing therefrom duringThat is toa eeepeus the automatic "operation oi the drawb'ench. J Theswitch K, therefore, constitutes manual meansior initiating theautomatic operations which followed the cam actuation ofthe'contactdevice A and the closing or" the contact Ad.

The switch L may be termed the grip return jog'switch and a momentarydepressing of'that switch establishes the circuitX,' mi9, switch L,

$20, :zz2l, x15, solenoid D", mlfi; all, contact Ea,

.rl8 and Y. That is to say, the momentary-ole pressing of the switch Lwillset up a situation, such as previously described; i. e., one whichinitiates a movement of the carriage it toward the die stand 1 6a, whichmovement continues only so long as the switch L-isxdepresse'd.

In Figure 26, I have" diagrammatically shown radius and, therefore,causes fluctuations or the:

current input to the motor M, such as may. be represented by the wavy'line S of Figure 27.

Comparison of Figures 27 and 28 will graphically illustrate an advantagegained. by' one feature of my'in'ventionr Eachfigurerepresents a powerinput curve,- suchas is traced by arecording wattmeter, where the motorinvolvedis actuating the grip-carrying carriage of a drawb'ench. Figure27 represents such a curve where the fluid coupling forming apart of thedrive mechanism, is adjusted withrelation to the amount of liquid in thepower chamber, so as to insure the delivery of sufficient energy fromthe motor 46 to occasion an effective operation of the drawbench underthe drawing conditions involved. In other words; the curve of Figure2'7illustrates power input during a draw, where the'drive includes a fluidcoupling in which thepower chamber is overfilled' for theimposed load.It also approximates a condition such as would be encountered wherethesproeket 45 of the drawbenchis connected to the operatingmo'tor by anordinary ornon-yielding form' of mechanical coupling.

The curves of Figure 2'7 disclosethat-normally the power input peaks toapoint T at the beginning of a draw, i. e., to a point considerablyabovethe power input required to c'ontinue the' draw after it is initiatedand well under way.

Even greater input peaks than illustrated'by-the" I- avoid the peakingat the beginning of the draw andthe result of the irregular torque con--ditions duringthe draw; by so adjustingthe device SB- that the extent orthedegree to which thepower chamber of the fluid coupling isfilled,

is such as to limit the power delivering capacity of the coupling to apredetermined maximum Here again, such conditions such-thatapredetermined:- rate of draw cannot-- be exceeded. As a result the sliebetween $1181 peller 37 and runner 35 will? increase for excess? loadsover the: predeterminedsmaximum "and decrease when the-load. is belowthe: pre'deters mined maximum; In -other wordsgwthe rate: ctr draw willvary as the loadw'conditionsrvary and will vary in such a way as tomaintain an apiproximately constant load onthe. prime moven' The curveS" of'Figure' ZSIiXYdiP" cates the power input under conditionsdescribed (motor' 46).

and it 'will be noted that the input peak, at'sthe' initiation of thedraw, is avoided; and that the irregularity in the fluctuations-"orinput,1- occa sioned'- by the sprocket chain drive, arematerialiy'decreasedw All this avoids sho'cks and-1- undue strainsand'materialiyrreduces the-amount of scrap occasioned-by breaking: thestock during: a draw.

In Figure 9 1 haveriilustrated. a somewhat modified arrangement ofapparatus; which: may beemployed for the purpose or controlling: the As;there:

operation of the fiuidicouplingt 36. illustrated; the manifold 55 andcommunicating:

- pi'pingare dispensed with, with the resultcthat actuatingfiuid'for'the" diaphragm* motor t'lis" delivered directly to thepressure cha1nberC4Ia-..

of that motor; from eith'er the'gradrU-switclr 65*or 65". respects tothe corresponding-device illustrated in Figures? and 10 ami theiintentis-to' so con trol them that the device 65 is ei-fectiive in de'liveringfiuid: to the motor 4''! at a' high'efp'res sure thanthat-orthefiuid sodelivered the:

device 65" As shown in Figure 9, the pipiirgwfifil" corre sponds to'thepiping53 ot Figureldandcam municates with source of I fluid; underpressure" (suchtas pressure'regulator 53) 'through'pipe sea; It alsocorninunijzaftesdirectly with chamber 41a of" motor 5:7. the-pipette andthe piping 5B which, as in Fi ure 10', also includes thevalves VI andV2; The velvet/Lin the position shown in Figure'Q; estab lishes'communication between the pressure" chamber: lie of them'otor' ti'l andan exhaust pipe:

13' but-is capable of'b'eing turned counter-clockwise to establishcomn'iunication between' its inlet port andthe'deliveryport-of the valveV2, while cutting 01f communication with the" exhaust pipe 13".

The'valve Vii functions exactly as the 'valve V2 of Figure 10 and is'capable of bein turned" counter-clockwise,'- from the po'sition shownin- Figure 9; thus cutting ofi communication between" the device 65-,and'the'valve V! and establishing communication. between that valveandthe de vice fifi and, through valve VI with the pressure chamber 47aof the motor M. The device-65' is: located iii branch'piping GT"whichicomrnunicat'es: with the source'of-high pressure fluid (pipe 53a)and; in' effect, constitutes a by-passaround'the device 55' when" thevalve V2 is in the" position shown in Figure 9 and the valve'Vt isturned-aquarter turn, counter-clockwise; from the; posi-' tion showninlthat'figure- In describing the operation-- of the apparatusillustrated in Figure 9}reference i'sxinad'e" to the wiring diagramofFigure 11. As to the' diagram of'Figure' 11,-.itis notedthatmany of theelectrical devices, diagrammatically illustrated as apart thereof, arethesam'e devices as-areillustrated in Figures 14 to 22' inclusive'andFigure ZS. Fo'r'tli'at reason. the ref erence characters employedthe" wiring diagram of Figure 11 are similar to' those:=

Each such switch is. similar in all" The device fi5 'interveries betweendiirerence, the relationship between each numeral and letter, employedas a reference character is reversed. In the description of theapparatus of Figure 9, I have assumed that a draw has just beencompleted and that the carriage I8 is standing at a point along its waysremote from the draw stand 58a. Under such conditions, the motor M,which drives the sprocket 65 and the draw chain 22, is idling becausethe fluid coupling 36 is ineffective, i. e., is not transmitting powerfrom the drive shaft 37 to the driven shaft 35'. However, the currentinput, requisite for the idling load, is passing from the line wire Xthrough lat, the motor M (46) 2a", the solenoid h of the contact deviceh, 350 and Y, illustrated in the wiring diagram of Figure 11. The amountof current traversing this circuit, however, is not sumcient to energizethe solenoid h and actuate the contact device h, with the result thatthe contact Ha is in a position such that electrical contact is'brokenbetween the wires 39:0 and 66m. The carriage I3 is not only remote fromthe die stand lea but the hook 225 is released from the draw chain 22and is held in its'uppermost position by the latch 25 (Figure 1).

With the parts in the relationship stated, the switch C (Figure 11) ismomentarily depressed thereby completing the circuit X, l3zc, switch G,Mr, 15x, solenoid D, like, it's, contact Ea of the contact device E, Himand Y. Closing the switch C has the same efiect, in connection with thewir-.

ing diagram of Figure 11 and the apparatus of Figure 9, as previouslydescribed in connection with Figures 10 and 12. That is to say, itstarts the grip-return mechanism so that the carriage l8 moves at fullspeed toward the die stand Ilia.

Energizing the solenoid D actuates the contact Da (Figure 19) andcompletes a holding circuit for the solenoid D which circuit is asfollows: X, 2620, contact Ba of switch device B, 2792, contact Da, 28x,29x, 21x, lzr, solenoid D, lean, I103, contact Ea, [8:13 and Y. Thisholding circuit is maintained during the movement of the carriage i8toward the die stand 56a and until the carriage is close to that stand.During this movement, the cam 24 engages and actuates the switch deviceA which, as previously noted, is adjustably mounted so that its positionalong the carriage way ll may be varied. Actuating the switch A movesthe contact Ad to complete the circuit X, 2631, contact Ba, 21m, contactDa, 28x, 29x, 2232, contact Ad, 23:13, 241:, solenoid F','25:c, I11,contact Ea, 18m and Y, thus energizing the solenoid F of the co tactdevice F, thereby establishing electrical contact between wires 323m and31s: and breakin electrical contact between wires 53m and 54:: of

Figure 11. 7

During this return movement of the carriage I8, the valves V! and V2 arein the positions illustrated in Figure 9. That is to say, the valve Viestablishes communication between the piping 56 and the exhaust pipe 13thus maintaining atmospheric pressure within the pressure chamber Maabove the diaphragm 49 of the diaphragm motor 4'! (Figure 3) and thevalve V2 is in the position to establish communication between thebranch pipe 5'3 and the piping 55.

Depressing the switch A also actuates devices not shown and therebyslows the movement of the carriage 18 toward the die stand iSa.Establishing the electrical contact between wires 30:: and 3L):completes the circuit X, 25:12, contact Ba, 27$, contact Ba, 28x, 30x,contact Fa,-

3lm, 32:0, 24:0, solenoidF, 25x, Hr, contact Ea,

I: and Y thereby maintaining the energization of the solenoid F. Thecompleting of the last mentioned circuit also energizes the solenoid VI"since wire 33a: is electrically connected to wire 3m. Under theseconditions, all three solenoids D, F, and .V I are energized. Energizingthe solenoid VI causes the valve VI to move a quarter turncounter-clockwise and thus close off communication between piping 56'and the exhaust pipe 13 and, at the same time, establish communicationbetween the piping 6'! and 56 through the valve V2 which is in theposition illustrated in Figure 9. This delivers fluid under pressure tothe chamber 41a of the diaphragm motor 41 direct from the control device65 and, consequently, actuates the diaphragm 69 (Figure 3) to extend thescoop tube at a rate and to a position designated by the pressure of thefluid so deliveredto the chamber lla. This occasions the delivery ofliquid to the power chamber of the fluid coupling (Figure 4) and rendersthe coupling effective in driving the draw chain 22 but at a relativelyslow speed. The hook 23 is, however, latched in its uppermost positionand the carriage l8 therefore, continues to move toward the die stand.

During this movement, the cam 24 engages and depresses the switchmechanism B which, like the switch mechanism A, is adjustably mountedalong the way I! of the carriage l8. Depressing switch'B simultaneouslyactuates both of the contacts Ba and Bb (Figure 16) so as to break theelectrical connection between the wires 26m and 27m and to establishelectrica'l' connection between'the wires 35xand 36:13; This breaks thecircuits supplying current to the solenoids D, F and VI but completesthe circuit X, 35s,:

contact Eb, 36x, 37x, solenoid-E, 3Bxand Y.

De-energizing the solenoid D actuates the contact Dc (Figure 19) tobreak electrical connection between the wires 21m and 28x;de-enerortends to move the valve Vi to the position to exhaust thepressure chamber 41a above the diaphragm 49, the results flowing fromthe energizing of the solenoid E are so nearly simultaneous with thede-energizing of the solenoid VI that the pressure chamber 41a is actuFor example,

ally. maintained under pressure. energizing the solenoid E actuates thecontact mechanism E to break electrical contact between the wires I11:and I811; but to establish electrical contact between the wire 42m and43:13.

This completes the circuit X, 35a:,'contact Bb,

36m, Mr, 42m, contact Eb,.43r, 52x, solenoid V2,

53m, contact Fb, 54a: and Y. It also completes the circuit to thesolenoid Vi since the wire 431: is electrically connected to the wire33a:- by'the wire 44:0. noids VI, E and V2 are all energized.

The carriage I3 is now contacting the die stand I.

lBawith the resultthat the rod 26 has actuated the, latch 25 to releasethe hook 23 and thereby couple the carriage to the draw chain 22 and thegrips l9 have engaged and gripped the stock i tobe drawn. The energizingof the solenoids VI It, therefore, follows that the sole amcea;

VI: and V2. establishes communication between.

the-pressure chamber flwoi ther mntor-dil (Fig.-

ure. .3) and; the sourceof Lfluid. pressure: 53a through. the device.65, theyvalvev'i, the valve;

Vi and thepipingfifif; 'Thi delivers fluid underpressure to thepressure; chamberd'i'aand the pressurexof the fluid; so sdelivered isadjusted by the device 5.5

The pressurerof. the. fluid delivered. by the devicezzliS ispreferablymaterially greatcrthan that delivered by the device; (i5! Wiiththeresult that thezscooptube is motonlyextended at :a more rapid..rate,.,in response. to thisiincreased pressure, but is also furtherextended with the result "that, under; the control of the device B5,.

sufficient: liquid will :be delivered to the power chamber. ofthe-.coupling tomaterially increase theeifeetivenessor" thefluidcoupl-ing as a power transmitting device and; to-accomplishthe-draw atfithe desired rate of speed; It should, however, be notedthat because of the time lag involved, thEn'hOQk. engages. the chain:22.1as the power chamber of the coupling; is; filling tothe extentdesignated bythectmtrol: device Baa-mi, for that reason, the is stillmoving at a relatively slow speed. soon: as the coupling is capableoftransmitting/.sufiicient poem to initiate the draw, the-carriage 18moves away from the diestand. Ida. in responses to the pull of the chain22; fihis=t-movement is initiated at' a very slow speed, although thecarriage; accelerates to the full .drawingrspeed as the power chamberfills; to.

'Ihexload'impnsed onithe motor M'ihythe drawingoperatumcincreasesz thecurrent-input to that. motor to thez extenlt that the. solenoid: h.' isenergized suffirientlyto actuate the contact device h andmovethencontact: Ha; into. electrical; en.- gagementi with the wires391* and 49m; This completes :a holding circuit for? the solenoids Vt,E. and: V2." and continue those. circuits:

after; the switch mechanism B is; released by: the: camz24=(asparriageb8 movestothe left.) thusbreaking, the. electrical connectionbetween the wines .3 51v. and 33m. The movementof the switch mechanism.3 establishes. the: electrical. connection between the wires; 26m and2700, but, this. is.

ineffective establishing an operating circuit because the contact Do is:open, breaking electrical connection between the wireszla: and 2811..

The carriage It continues: its movement to the lef-truntil; the drawcompleted, at which. time.

the motor M isrelieved: of-the draiwing. load: with a resultant decrease:in the: current input to the moton. Thistle-energizes the solenoid. itwhich results in aymovement of contact device H such, that the: contactHm moves out of electrieal; connection the wires. 39m and 49s..

holding circuit'for the-solenoids 24 V I", E and V2 de-energizing. thesame witlithe result that each of the valves V1 and. V2 is returned: tothe position, illustrated in Figure 9,

and the contactv Ea moves to again establish:

electrical contact between the wires .l'lcr and 18x. Thecontact Eb.movesto break electrical contact between the wires 42a: and 43x thuspreventing re-establishing the .last mentioned holding circuit. Thecompletion o'f the draw relieves the chain. 22 of the draw load. andthis permits it to drop: away from or release itself from the.

hook 23, which, as previously noted, is held in the raised position bythe latch 25.

With the mechanisms in the positions described, the onlyv efiectivecircuit i's'that including the motor M, (X; 1.0:, motor M, 2r, solenoidh, 3x.

and Ys) but, asnoted, the currenttraversingthat.

circuit isrreduced to: the amount. necessary for operating the motorunder minimum load :conditions. and as a resultsolenoid; his-ineifective.

Depressing the push button or draw reset switch J will, under suchconditions, establish the circuit X, 591:, switch J, 6011:, M02, 37x,sole.-

noid. E, 3-82: and Y which energizes the solenoid.

Eand, through the action of the contact device E, re-establishes thecircuits for energizing theithree solenoidsvl, E, and V2, and,therefore, the switch J may be employed as an emergency switch forre-establishing the adjustment of the mechanisms essential for operatingthe carriage under drawing load, and independently of the position ofthe carriage [8 along its way It will also be understood. that, afterthe completion of a draw and after all circuits have been-opened, exceptthe circuit supplying current to the motor M at mini-mumload. input,depressingthe push button C will initiate another drawing cycle bycompleting the circuit through the solenoid D and through the contactEa, which is closed under the conditions indicated. As previously noted,the depressing of the button C will deliver current (byinstrumentalities notshown and forming no part of the present invention)to the motor actuating the grip-return mechanism with the result thatthe drawing cycle will be initiated by starting the carriage 4-8 to moveat full speed toward the die head We.

Depressing the: push button or hook reset. switch K establishes thecircuit X, the, switch K, 522:, Mm, 32x, 24x, solenoid F, 255;, Hm,contact Ear, I89: and. Y. Energizing, the solenoid-=1 opens the contactbreaking the circuit for solenoid V2." and. closes the contactFw therebydelivering current. to. solenoid D through the wires Mm, 3hr, contactFa, 3303,, 29:12, 2131., 15m, solenoid D, Ilia, Um, contact: E12,. i851:andiY; It also establishes a current flow from the wire 4450 through thewire 38x, solenoid VI", wire 34a: and Y, thus energizing the solenoid.V1 and turning the valve Vi a quarter turn. counterclockwise thusestablishing communication 'be-- tween the device 6 5' and the pressurechamber of the motor 41. Under such conditions, the scoop tube is movedbythe motor- G'i to a position such as to partially fill the powerchamber 37a and, therefore, drive thechain 2-2. at a. slow or hook-inspeed.

The switch L has been termed the grip-re.- turn jogswitch. Its functionis to interrupt other operative circuits for the purpose of moving thecarriage liibac'k toward the die head 16a. When moved to the positionwhich establishes electrical contact between wires [9m and 21m, it

. 'establishes-the-circuit X, like, 'switchL, 20c, 2la:,.-

' I51, solenoid D, [6:2, 110:, contact Ea, 18a: and 'Y. That is to say,the momentary depressing of switch L sets up a circuit through thesolenoid D of the contact device Di. e., a circuit similar to onepreviously described--and initiates a return movement of the carriagetoward the die stand 16a which movement continues so long as switch L isso depressed.

From the foregoing description, it is apparent that the ap aratus,diagrammatically illustrated in each of Figures 9 and 10 constitutes apart of a system of co-operating instrumentalities which occasions theautomatic initiation of the draw with a minimum of shock and at a ratesuch as avoids subjecting either the drawn stock or the drawingmechanisms to undue strains. Each such apparatusor system initiates thedraw at a low rate of speed and then accelerates the drawing mechanismto the desired drawing speed. The apparatus of Figure 10 is effective inoccasioning a more rapid acceleration of the carriage l8 than theapparatus of Figure 9, due to the fact that it occasions a rapidextension of the scoop tube under the control of one device and thenshifts the control to another device which positions the tube and,therefore, designates the extent to which the power chamber of thecoupling is filled with liouid from the annulus. In this way, thefilling of the power chamber is accelerated and, as a result, the periodof the operating cycle of the drawbench is shortened and the drawbenchis, therefore, ca-

pable of doing more work in a designated period of time.

While I have illustrated two forms of apparatus for carrying out myinvention and have described the procedures involved, it will beunderstood that various changes, additions, substitutions and omissionsmay be made in both the apparatus illustrated and the procedure definedwithout departing from the spirit and scope of my invention as definedby the appended claims.

What I claim is:

l. A method of operating a draw bench equipped with a die stand and agrip-carrying carriage movable toward and away from said stand, a chainfor actuating said carriage during the drawing operation away from saidstand and a sprocket for driving said chain, which consists inoperatively coupling the carriage to said chain to accomplish a drawingoperation while saidchain is moving at a slow speed; then increasing thespeed of said chain while so limiting the driving power applied to saidsprocket that the rate of angular movement of said sprocket variesinversely with the variations in the effective driving radius of saidsprocket, decreasing as the effective radius increases and increasing asthe effective radius decreases.

2. A power-transmitting assembly including a constant speed motor; adriven mechanism, and a fluid coupling comprising a rotatable impelleroperatively coupled to said motor, a rotatable runner operativelycoupled to said driven mechanism, a power chamber formed within saidimpeller and runner, a reservoir casing secured to and rotatable withsaid impeller and a scoop tube operating within said casing to deliverpower-transmitting liquid therefrom to said power chamber; and a controlmechanism for extending said tube to diiierent positions with relationto a liquid annulus formed in said casing during rotation thereof incombination with a device for controlling said control mechanism toextend said tube at one rate toward a predetermined position withrelation to such annulus; a separate device for controlling said.control mechanism to extend said tube at a different rate to a differentposition with relation to such annulus; and means responsive to movementof said driven mechanism for shifting the control of said controlmechanism from one of said nism during its forward movement; a fluidcoupling between said motor and said mechanism for transmitting power tosaid mechanism and moving the same throughoutsuch forward movement, saidcoupling comprising a rotatable impeller, operatively coupled to saidmotor, a runner operatively coupled to said mechanism, a

power chamber enclosed by said impeller and said runner and means fordelivering powertransmitting liquid to'said power chamber andcontrollable to adjust the extent to which such chamber is filled withsuch liquid during rotation of said impeller; a'control mechanism forrendering said liquid delivery means effective and for controlling therate of delivery of liquid thereby to said power chamber; a devicerendered effective during the return movement of said driven mechanismto control said control mechanism to actuate said liquid delivery means'to deliver liquid to said power chamber at a predetermined rate; asecond device rendered effective during the return movement of saiddriven mechanism to control said control mechanism to actuate saidliquid delivery means to deliver liquid to said power chamber at adifferent predetermined rate; and means actuated by said drivenmechanism during the return movement thereof for actuating said firstmentioned device to control said mechanism and then to shift suchcontrol to said second device.

4. A power-transmittlng assembly including a driven mechanism movable intwo directions, i. e., a forward movement under load and a return,load-free movement back to a load-receiving position; means for movingsaid driven mechanism throughout said return movement; a constant speedmotor for impelling said driven mechanism throughout such forwardmovement; a fluid coupling for transmitting power from said motor tosaid mechanism to thereby impell said mechanism throughout its forwardmovement, said coupling comprising a rotatable impeller operativelycoupled to said motor, a rotatable runner operatively coupled to saiddriven mechanism, a power chamber formed within said impeller and saidrunner, and a reservoir casing rotatable with said impeller; a scooptube operating within said casing todeliver power-transmitting liquidtherefrom to said power chamber; a control mechanism for extending saidtube to different positions with relation to a liquid annulus formed insaid casing during rotation thereof; in combination with a devicerendered effective during the return movement of said driven mechanismfor controlling said control mechanism to extend said tube toward apredetermined, annulus-engaging position within said casing; a seconddevice for controlling said con-

